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Regression to the mean in progress reports

Research Methods › Statistics number needed to treat heterogeneity confounding effect size worked example

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h.almeidaTL2Member10 Apr 2025#1

On the subject in the title: Regression to the mean in progress reports Working notes rather than a conclusion.

Something about regression does not reconcile and I would like a second pair of eyes before I decide which half is wrong.

Two sources, both reputable, giving figures that cannot both be right unless they are measuring different quantities. My suspicion is that they are, and I cannot see how.

58 likes 16mo

c.okaforTL3Regular5 Jun 2025#17

Nicolaides, post #9: Reading this regression thread as someone who came in with a fixed view: the third and seventh replies moved me and the confident ones did not. Go to post

Confounding: a third variable explains an apparent association. In randomised data, randomisation balances confounders. In observational data, confounders can be adjusted for but unknown ones cannot.

If anyone has run this properly I would rather read that than my own guess.

30 likes in reply to #9 14mo

f.abrahamsenTL2Member21 Jun 2025#23

Seconded. It reads as careful rather than confident, which is the right register.

28 likes 13mo

n.zielinskiTL28 Jul 2025#30

On regression, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one.

27 likes 13mo

s.cabreraTL216 Jul 2025#33

Regression to the mean explains a large share of apparent improvements in anything selected for being extreme. It is not a statistical curiosity; it is the default explanation.

The reasoning is more useful than the number, which is why I have shown it.

27 likes 12mo

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About the Statistics categoryResearch Methods › Statistics · 8 replies

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